Refrigerating process and apparatus



Feb. 9, 1932. R. w. DAVENPORT I REFRIGERATING PROCESS AND APPARATUS Filed Nov. 25, 1930 'INVENTOR. o/750m Wfim enporf JM f. WWW l I Patented Feb. 9, 1932 UNITED LSTATES PATENT, OFFICE RANSOM W. DAVENPORT, F DETROIT, MICHIGAN, .ASSIG-N'OR TO CHICAGO PNEUMATIC TOOL- COMPANY, OF NEW YORK, N. Y, A CORPORATION OF NEW JERSEY REFRIGERATIN G PROCESS AND APPARATUS Application filed November 25, 1930. serial no. 497,968.

This invention relates to the transforming of heat with particular reference to refrigerating systems of the closed cycle type utilizing as a working substance a volatile liquid and a gas inert to and insoluble in the liquid, the operation being in accordance with the vapor-gas principle disclosed-in various patents previously'issued to me including Patent No. 1,619,196, dated March 1,1927.

The invention comprises both a process and apparatus for practicing the process.

In my previous disclosures the liquid and vapor-gas mixtures have been fed in a more or ;-less hit-or-miss manner through an expansion nozzle of the fixed orifice type into the evaporator. This lack of orderly arrangement or proportioning of the components of the working substance has under certain conditions produced irregularities in the operation of the system. Attempts haveqalso .been made in the past both by myself and by others with this and with other systems to cool the products of the condenser below the temperature of the environment by heat interchange with a portion of the low side apparatus. Difficulties have. invariably been encountered through the tendency of the interchanger to do a disproportional amount ofcondensing, since practically an unlimited supply of the vapor passes out of the. condenser into the interchanger.

One object of the invention is to devise 7. improved ways and means for utilizing the working substance in a refrigerating system operating on the vapor-gas principle. Another object is to provide improved methods and apparatus for feeding the contents of the condenser into the evaporator in such a system. Still another object is to pre-cool the condenser products through heat interchange with the evaporator without having the latter do a disproportionate amount of condensing. Other objects will be apparent from the detailed description which follows.

Instead of feeding the liquid and the vapor-gas mixture out of the condenser in a hit-or-miss fashion, the working substance is organized into an orderly. series of bodies, first of liquid and then'of vapor-gas mixture to form a broken-column of liquid and gas which may be conducted while still in order the expansion device. In the preferred ar rangement, means associated with the condenser are provided for dripping the liquid products thereof into a funnel leading into a tube or conduit having a bore small enough to allow the liquid to fill or close the same. Each drop thus forms a piston or slug in the conduit and between each two liquid slugs is disposed a slug of the vapor-gas mixture comprising the remaining product of the condenser. By simply confining the seriesof alternating slugs in the small bore tube or conduit, the same may be conducted intact through the interchanger and thence to the expansion device. Thus the supply of the working substance to the'expansion device is metered in proportions fixed by the .rate of dripof the liquid component into the funnel and a hitherto impossible result is attained.

In order to illustrate. the invention one concrete embodiment thereof is shown in the accompanying drawings, in which:

1 Fig. 1 1s a diagrammatic view of the sysany known or suitable type, it merely being requisite that feeding device D discharge the products of condenser C beneath the level of a body of refrigerant liquid in evaporator A and provide a fixed orifice or nozzle of suitable size to pass both the gaseous and liquid to. Interposed' between condenser C and feeding device D are means for forming the products of condenser C as conducted thereproducts of the condenser into a stream comprising a series of alternating slugs of liqaid and gas. As shown, the means comprise a separator 3 providing a chamber having an inlet 4 at the top for receiving the products of condenser C. In spaced relation to inlet 4 and beneath the same is a receptacle 5 for the liquid or condensate, which recep: tacle on its lower side has a metering nozzle 6 through which the liquid issues intermittently in drops of predetermined size. These drops fall into a funnel 7 serving as the outlet for separator 3, which funnel directs the drops of liquid into a conduit 8 leading to expansion device D and having a bore so small that each drop fills the bore and forms therein a liquid piston or slug. Since the interior of separator chamber 3 is filled with a gaseous component of the working substance and any residual vapor which has not been condensed, which gaseous products are under pressure from the discharge of pump B, the slugs of liquid move through conduit 8 toward expansion device D and the intervening space between the slugs is filled with the gaseous products of the working substance with the result that a stream of alternating slugs of liquid and gas passes from the separator 3 to expansion device 10.

An improved refrigerating efiect is produced by reducing the temperature of the stream of alternating liquid and gaseous bodies before they pass through expansion nozzle D. In Fig. 1 a portion of conduit 8 is brought into direct contact with a portion of the low pressure temperature side of the system, namely evaporator A. As shown, the movement of fluid to expansion valve D is countercurrent to the movement of fluid away from the expansion device.

In Fig. 2 is disclosed a self-contained household refrigerator outfit embodying the apparatus and arranged to operate in accordance with the improved processdiscloseddiagrammatically in Fig. 1. The outfit comprises the refrigerator cabinet E having a food storage compartment 6 and amachine compartment 6 disposed beneath the refrigerator compartment. The means for extracting heat from refrigerator compartmente may comprise a suitable evaporator consisting of a cold box a to provide for the freezing of liquids and an evaporator coil (1', the same being disposed vertically in series adjacent one wall of the refrigerating compartment as shown. The evaporator members are connected by a pipea to a motor pump unit I) disposed in machine compartment 6 which discharges through a pipe 6" into a condenser c which in the present instance is secured to the exterior of'the refrigerator, as at the back, and arranged to be cooled by a natural draft. Condenser c drains into a separator 5a similar in all respects to' separator 5 of Fig. 1 and operating in the same manner.

Gonduit 8a leads from separator 5a through the back wall of refrigerator E to the interior of the latter and has a coil 86 suitably arranged in heat exchange relation with cold box a. In the present instance coil 8?) is secured to the exterior of'the cold box. Coil 86 leads to expansion device cl which connects directly with cold box a.

From the above it will be apparent that the expansion device is always fed at a regular and proper rate with the components of the working substance in proper proportion, that an interchanger may be used to good thermodynamic advantage since only a restricted or metered amount of vapor can be removed from the condenser, and that the interchanger accordingly may operate very much below condenser temperature without robbing the latter of its vapor since the advancing spaced pistons or slugs of liquid form seals and prevent the inter-changer from withdrawing vapor in inordinate amount from the condensen /Vhile the invention has been herein disclosed in both its process and apparatus aspects in what is now considered to be a preferred form, it is to be understood that the invention is not limited to the specific details thereof but covers all changes, modifications, and adaptations within the scope of the appended claims.

T claim as my invention:

1. In a closed cycle heat transforming system having high and low pressure parts and utilizing as a working substance a volatile liquid and an incondensible gas which is in-'- sol'uble in the liquid, both components of the working substance being circulated entirely through the system, the process steps ofseparating the working substance into a series of alternating liquid and gaseous bodies and conductingthe series of alternating bodies from the high pressure side to the low pressure side of the system.

2. In a closed cycle heat-transforming system having high and low pressure and temperature parts and utilizing as a working substance a volatile liquid and an incondensible gas which is insoluble in the liquid, both components of the working substance being circulated entirely through the system, the process steps of separating the workingsubstance on the high pressure temperature side of the system into a series of alternating liquid and gaseous bodies and bringing said series of bodies into heat exchange relation with the low temperature pressure side of the system while conducting said series from said high pressure temperature side to said low pressure temperature side.

3. In a refrigerating process utilizing as a working substance an evaporable liquid and an incondensible gas and involving the feeding of the working substance from a' condenser to an evaporator through an expansion member having a continuously open port theprocess steps comprising forming said working substance as 1t issues from the condenser into, a series of alternate liquid and vapor-gas bodies and conducting said series of bodies to the expansion member.

4. In a refrigerating process utilizing as a working substance an evaporable liquid and an incondensible gas and involving the feeding of the working substance from a condenser to an evaporator through an expansion member having a continuously open port the process steps comprising forming said working substance as it issues from the condenser into a series of alternate liquid and vapor-gas bodies, bringing said series of bodies into heat exchange relation with the evaporator, and conducting said series of bodies to the expansion member.

5. In a refrigerating process utilizing as a working substance an evaporable liquid and an ineondensible gas and involving the feeding of the Working substance from a condens-- er to an evaporator through an expansion member having a continuously open port the process steps comprising metering the liquid component of the working substance as it issues from the condenser to form a series of liquid bodies of predetermined size, spacing said liquid bodies by intervening bodies of the gaseous component of the working substance, and feeding the stream of alternating series of liquid and gaseous bodies through said ex pansion member to said evaporator.

6. In the process of producing refrigera- 'tion by the use ofa working substance comprising a liquid and a gas substantialy inert to and insoluble in said liquid, the steps of separating a stream of the working substance into alternate liquid and gaseous bodies and expanding the stream of bodies into a body of the liquid. 7. In the process of producing refrigerationby the use of a working substance comprising a liquid and agas substantially inert to and insoluble in said liquid, the steps of separating a stream of the working substance into alternate liquid and gaseous bodies, extracting heat from the stream of bodies, and expanding the stream of bodies into a body of the liquid.

8'. In a refrigerating system utilizing a working substance having liquid and gaseous components and comprising a condenser, an

evaporator, an expansion device having an open port between said condenser and said evaporator, means for forming the working substance .as it leaves said condenser into a series of liquid bodies alternating with.

bodies of vapor-gas, and means conducting the stream of bodies intact to said expansion device.

9. In a refrigerating system utilizing aworking substance having liquid and gaseous components and com-prising a condenser,'an

'said evaporator.

evaporator, an expansion device having an open port between said condenser and said evaporator, means for forming the working substance as it leaves said condenser into a series of liquid bodies alternating with bodies of vapor-gas, and means conducting the stream of bodies so formed first into heat exchange relation with saidevaporator and then to said expansion device.

10. In a refrigerating system utilizing a evaporator, an expansion device having an open port between said condenser and said evaporatorflneans forseparating the working substance as it leaves said condenser into its liquid and gaseous components, means for metering the separated liquid, and means for conducting the metered liquid in bodies spaced by the gaseous component to said expansion device.

12. In a refrigerating system utilizing a working substance having liquid and gaseous components, an evaporator containing the liquid component ofthe working substance, a pump connected to said evaporator for effecting vaporization of said liquid component, a condenser into which said pump discharges, a separator adjacent the bottom of said condenser, a conduit leading from said separator into which a series of alternating bodies of the liquid and gaseous components. of the condenser are discharged, and an expansion device to which said conduit leads and having an open port communicating with a said evaporator.

13. In a. refrigerating system utiliziiig a working substance having liquid and gaseous components, an evaporator containing the liquid component of the working substance, a pump connected to said evaporator for effecting vaporization of said liquid component, a condenser into which said pump discharges, a separator adjacent the bottom of said condenser, a conduit leading from said separator into which a series of alternating bodies of the liquid and gaseous components of the condenser are discharged and an expansion device to which said conduit-leads and having an open port communicating with said evaporator, a portion of said conduit being disposed in heat exchange relation with 14. In a refrigerating system. operating on components and comprising a'condenser, an

device, and an evaporator connected together into a closed cycle system, means interposed between said condenser and said expansion device for separating the products of condenser into a series of alternating bodies of liquid and of vapor gas and for determining the size of the liquid bodies.

15. In a refrigerating system operating on the vapor-gas principle and having a com pressor, a condenser, a fixed orifice expansion device, and an evaporator connected togetherinto a closed cycle system, means interposed between said condenser and said expansion device for separating the products of the condenser into a series of alternating bodies of liquid and of vapor-gas and for determining the size of the liquid bodies, and means bringingsaid bodies into thermal contact with said evaporator before they reach said expansion device. 1

16. In a refrigerating system operating on the vapor-gas principle, a separator for interposition between the condenser and the expansion device of the system, said separator providing a chamber having an inlet for communication with the condenser, a receptacle therebeneath for liquid having a'metering nozzle for discharging the liquid intermittently, and a funnel shaped outlet beneath said nozzle having a conduit extending therefrom of a size to maintain the discharge from said separator as a series of alternating liquid and gaseous bodies.

17. In a refrigerating system of the evaporator-compressor-condenser type the process of precooling the products of the condenser before admission to the evaporator by bringing them into heat exchange relation With the evaporator and preventing unlimited Withdrawal of vapor from said condenser.

' 18. In a refrigerating system of the evaporator-compressor-condenser type the process of precooling the products of the condenser before admission to the evaporator by bringing them into heat exchange relation with the evaporator and utilizing the condensate to meter the gaseous products of the condenser moving to the evaporator.

19. In a refrigerating system having a compressor, a condenser, an evaporator, and an expansion device connected together to form. a closed cycle system-utilizingvolatile liquidand an inert gas 'as the Working substance, a conduit arranged to bring the products of said condenser into heat exchange relation with said evaporator before conducting the same to said expansion device and means, preventing free movement of the gaseous products of the condenser in said'conduit.

20. In a refrigerating system having a com.- pressor, a condenser, evaporator, and an expansion device connec ed together to form a closed cycle system utilizing volatile liquid was 

